Over the past 10 years our center has been involved in multiple projects with collaborators interested in various aspects of neurobiology. Anatomical structures and pathological processes have been successfully investigated. Our improved technical skills have elicited our users who are now approaching us with more specific and demanding tasks; We are increasingly approached by neurogeneticists who wants us to characterize anatomy as well as pathology in various transgenic rodents with known genetic defects. We are being challenged by these projects not only because of the small-sized mouse brain but also because of the need to apply our MR proton stain knowledge base more efficiently and accurately. The biologist raises specific questions, i.e. is there atrophy? gliosis? neuronal degeneration? demyelination? and desires specific answers. The typical biologist is obviously incapable of translating this information into exact MR parameters. The MR physicist, on the other hand, often has insufficient knowledge of the biology involved to predict the outcome of a given MR proton stain. To improve efficiency and quality of future neuropathological projects we are proposing to take a more systematic approach by creating a neurohistological database which will make explicit connection between specific proton stains and well-characterized pathologies. Not only will we expand our general knowledge on contrast mechanisms we will also gain valuable "diagnostic" information for future projects.